Polypeptides responsive to isoprenaline in mouse parotid glands

Abstract

622nd MEETING, LEICESTER 95 I As isoprenaline is known to modulate the expression of mRNAs for members of the 'proline-rich' protein (PRP) family in rats (Meunzer et ul.. 1979) and induce at least three PRPs in mice (Mehansho et al., 1985), a rabbit anti-PRP IgG preparation was used to identify PRP in vitro products. All six 'early' in vitro products were immunoprecipitated while the 'late' species was not. Fig. 1 illustrates the translational activity of the isoprenaline regulated mRNA for the PRP of M , 41 000 during the course of isoprenaline treatment.To analyse the effect of isoprenaline upon parotid gland gene expression further, a cDNA library in pBR322 was made from isoprenaline 'stimulated' parotid poly(A+ )RNA. Sixty cDNA clones derived from abundant isoprenaline regulated mRNAs were identified by differential colony hybridization using [32P]cDNA probes made from 'stimulated' and 'non-stimulated' parotid poly(A+ )RNA. The cDNAs were then analysed with restriction endonucleases and grouped into families of homologous sequences by colony cross-hybridization using selected cloned cDNAs as probes after labelling with [32P]dCTP by nick translation.The cDNAs for these isoprenaline regulated sequences represent useful tools for studying P-adrenergic regulation of mRNA abundance.